A wide variety of different forms of electric soldering irons have been proposed in the past with the result that the art has reached a relatively advanced state. Somewhat recent forms of such irons are disclosed, for example, in U.S. Pat. Nos. 3,287,541 (Weller et al); 3,336,462 (Fuller); 3,410,472 (Weller et al); and 3,786,229 (Hombrecher).
The desirable characteristics of an electric soldering iron involve a variety of considerations. For example, the tip of the iron should be easily removable for convenient replacement or refurbishing. As a related consideration, the entire iron should be relatively simple and easy to assemble and break down so as to facilitate the initial manufacture as well as subsequent repair. Another important consideration involves effectively heat shielding or insulating the handle so that the user's hand is not subject to discomfort or injury. Other considerations involve economy of manufacture, safety in use, effectiveness to provide a heated working surface at the tip, and the ability to withstand elevated temperatures and use for long periods of time. Finally, the iron should be compact, convenient to use, and rugged, specifically with regard to the cord serving to energize the iron.
Although irons of various structural forms have been proposed with the objective of satisfying these considerations, a need continues to exist for an improved electric soldering iron. In general, the iron of the present invention affords such an improved structure.
The present invention involves structural aspects of both the front end and the handle of a soldering iron. Somewhat more specifically, the tip of the front end (providing the heated working surface) is grooved annularly to receive a holder ring which is then clamped between a collar and a front-end barrel that contains the heating element embedded in magnesium oxide. Conductors extend to plug in contacts that are rigidly supported.
At a location opposed to the tip of the front end, the barrel defines a radial flange which is fixed to the ends of a pair of mating handle members. In combination, the handle members define an irregular passage for lockingly engaging the sheathed conductors passing from the front end through the length of the handle.
The handle is held together in the disclosed embodiment by a pair of sliding collars, one of which incorporates ridges to define an air space between the handle members and the collar which also incorporates a flange to afford additional heat shielding and furthermore to provide cornered edges which inhibit the iron from rolling.